Electromagnetic switching device



Sept. 1l, 1934. Q D MILLER I 1,973,090

\ ELECTROMAGNETIC swITcHING DEVICE Filed March 29. 1933 /NVENTOR D. D.MILLER A T TORNEV Patented Sept. 11, 1934 UNITED STATES PATENT OFFICEELECTROMAGNETIC SWITCHING DEVICE Application March 29, 1933, Serial No.663,273

12 Claims. (Cl. 20d-104) This invention relates to electric switchingdevices and more particularly to electromagnetic relays.

In electrical systems generally and in telephone systems particularly,the electromagnetic relay plays an important part and is one of the mostextensively employed switching devices in communicating systems.

In all modern industries, for example, the automobile industry, wherethe manufactured product is constituted of a plurality of independentlyand separately developed parts, it has been found practicable to designthe independent parts in such a manner that they readily adaptthemselves to straight-line assembly methods.

The electromagnetic relay is essentially made up of a core, coil,armature, contact springs and mounting bracket, the last serving tosupport the contact springs. To adopt straight-line assemblymethods inthe manufacture of relays, it is therefore necessary that each of theconstituent partsbe designed as a separate unit and in such a mannerthat such parts may be carried in stock as complete entities, to beselected and assembled in progressive steps to lform the final desiredstructure.

Heretofore, in the design of the well known flattype relay, it has beenimpossible to effect a complete assembly by progressive assemblymethods. Owing to the particular conformation of the flattype relaycore, which is provided at one end with an enlarged pole-face area andat the other end with integral lateral projections forming mountingmeans for the contact springs, it was impossible to provide for the useof form-wound coils or coils which were wound prior to their assembly onthe core.

Another diiiiculty heretofore experienced in connection withstraight-line assembly methods as applied to relay construction was thefact that it was desirable to pre-assemble various contact springcombinations so that they could be mounted as units on the relay ratherthan build the combination on the relay, one spring element at a time.

It is, accordingly, the object of this invention to improve the designof flat-type relays to permit the use of form-wound coils, andpreassembled spring combination units and to provide for the completeassembly of the relay parts in accordance with modern progressiveassembly methods.

'This object is attained in accordance with features of the invention bythe provision of a relay core having a flattened or cut-away front endportion to provide a relatively large pole-face area and to permit aform-wound coil to be slipped over the core from the front end, and apair of contact-spring-supporting plates provided with centrallydisposed and opposing recessed 6o portions which cooperate to form ahousing for the rear end portion of the core. The provision of twocontact-springsupporting plates renders it possible to pre-assemble andmount the Contact springs on the relay and to permit the removal ofeither the upper or lower spring combination without disturbing theentire contact spring assembly.

Another feature of the invention resides in the use of forwardlyextending short spring members mounted on one side of the relay whichserve as terminals for the relay coil winding. These springs areprovided near their forward ends with projecting lugs or test clipprongs, and nearer their rear ends with upturned lugs to which the coilends are soldered. The provision of the test clip prongs on the forwardend of the terminal spring permits relay tests to be made in front ofthe relay rack and provides a convenient means of supporting the testclips.

These and other features of the invention will be readily understoodfrom the following detailed description made with reference to theaccompanying drawing in which:

Fig. l is a top plan view of a flat-type relay embodying the features ofthis invention;

Fig. 2 is a 'side elevation of the relay structure shown in Fig; 1;

Fig. 3 is a view similar to that of Fig. 2 with certain elements of therelay omitted and partially in section to more clearly illustrate thefront and rear end construction of the core and the manner in which theseparate spring-supporting brackets are supported thereon; and

Fig. 4 isa rear elevation of the relay structure 95 shown in Figs. 1 and2.

Fig. 5 is an exploded View of the relay rear end showing the manner inwhich the spring mounting bracketsare mounted on the relay core.

The body portion of the core l0 is cylindrical 100 in shape being cutaway at the front end to provide a relatively large pole-face area lland with its rear end portion flattened out to serve as a seat uponwhich the two spring-supporting elements l2 and 13 are supported andbetween which 105 a reed-type armature hinge le is clamped. A form-woundcoil 15 is slipped over the core from the front end, the rear end of thecore having Welded thereto a mounting bracket' 16.

Each of thev brackets 12 and 13 independently 110 -to their respectiveplates l2 and 13 to be carried in stock as separate entities, so thatwhen a particular spring combination is desired, the two plates 12 and13, carrying the spring sub-combinations which cooperate to form thedesired combination, are taken from'stock and secured to the core end bymeans of the screws 21. It will also be observed that shouldit befoundnecessary to remove the lower pile-up 17 to replace it with a differentsub-combination it is only necessary to remove screws 2l and lift thebracket 13 oiT the core; This act though freeing the upper bracket fromthe core does not in any way disturb therelationship of the springswhichconstitute the upper pile-up 18. Y

As seenin Figs. 4 and 5 the plates'12 and 13 are centrally arched toallow for the rear end of the core lil to which the plates are secured.

Interposed betweenthe upper plate l2 and the corelO is a reed-type hinge14 to which issecured the armature'22.

On the iront end or corel() is mounted a well known type of air-gapadjusting device comprising screw 23 and its associated nut 24.

The terminals for the coil winding consist of the two spring members 25.`Each member 25 is provided with an upturned lug 28 to which is solderedone end of the coil winding. At their front ends, the terminalV springs'25 are provided with an extendingportion 29 `which constitute test-clipprongs/by virtue of which the relay may be tested conveniently` by oneperson while in a position to observe the armature and contact springaction. `Heretofore the relay was tested by means of the lugs 28 whichare notv accessible to the `test man from, Vthe iront of the Y relayrack' so that it was necessaryduring tests for the test man to firstapply test clips to the lugs 2S at the rear of the rack and then go tothe front of the rack to observe the relay operating or else the testrequired the services of two men. The test clip prongs 29 provide aconvenient means for permitting the relay to be tested and observed byone person. ,j

What is claimed is: Y

l. An electromagnet having a cylindrical core provided at one end with aflattened pole-face and at the other with a reduced portion, a coiladapted to be slipped over the core, a pair of contact-spring-supportingbrackets having opposing recessed portions whichcooperate to form ahousing for the reduced portion of the core, each of said bracketssupporting an independent pile-up of spring contacts and an armatureactuated upon energization of said coil for operating said springcontacts.

2.` An electromagnet comprising a core, a coil carried by said core, aplurality of `spring pileups, an armature for actuating said springsupon energization of said coil and a bracket for each of Ysaid springpile-ups, said brackets being sup.- ported on said core. y

3. An electromagnet comprising a core, a coil carried by said core, aplurality of spring pile-ups, an armature for actuating said springsupon energization of said coil. a bracket for each Aof said springpile-ups mounted on said core, and independent fastening means forsecuring each of said pile-ups to its respective bracket.

4. An electromagnet comprising a core, a coil carried by said core, a.plurality of spring pile-ups, an armature for actuating said springsupon energization of said coil, a bracket for each of said springpile-ups mounted on said core, independent fastening means for securingeach of said pile-ups to its respective racket, and means for securingsaid brackets on said core so as to eiect a single spring combination ofsaid plurality of spring pile-ups. l

5. An electromagnet comprising a core, a coil carried by said core, aplurality of spring pile-ups, an armature for actuating said springsupon energization `of said coil, a bracket carried by said core andsupporting a spring pile-up on one side of said electromagnet, a secondbracket carried by said core and supporting a spring pile-up on anotherside of said core, said brackets being separately removable from saidcore and said pileups cooperating to effect a single spring combinationwhen mounted on said core and independent fastening means forV securingeach of said pileups to its respective bracket and for securing saidbrackets to said core.

6. An electromagnet comprisinga core, a coil carried by said core, aplurality of spring pileups consisting of alternate spring members andinsulating separators, each of said pile-ups constituting a springsub-combination, an armature for actuating said springs uponenergization of said coil, a bracket supporting one of said springsub-combinations on one side of said electromagnet, a second bracketsupporting another of said spring sub-combinations on another side ofvsaid electromagnet, said spring sub-combinations being separatelyremovable from said core and serving, when mounted on said core, as asingle spring combination, independentV fastening means for securingsaid spring pile-ups to their respective bracket, an armature hingesecured to said armature and interposed between'said brackets, and meansfor securing said brackets and said armature hinge to said core.

7. An electromagnet having a core, a coill mounted on said core andterminal springs for said coil, said springs beingprovided withupturnedmlugs to which the ends of said'coil are secured and with testprongs extending forwardly from said lugs and integrally formed with,said springs, said forwardly extending prongs providing means forconveniently testing said coil.

8. In a'relay, a magnetic core having a head portion disposed at one endthereof and a shank portion disposed at the other end'thereof, a formWound coil disposed upon said core, a second head portion of magneticmaterial having an aperture therein for receiving said shank, and springcontacts and terminals mounted upon said second head portion andelectrically connected to said coil.

9. In a relay, a magnetic core arranged to receive a form wound coil andhaving a head disposed at'one end thereof and a shank disposed at theother end thereof, a head portion of-magnetic material composed ofmembers secured together and having diametrically opposed groovesforming an aperture for receiving said shank, and contact springs,terminals and an armature securedA to said detachable head portion, theterminals being electrically associated withsaid coil.

l0. In a relay, a core having a head portion disposed at the end thereofand a shank disposed at the other end thereof, a form wound coildisposed upon said core, an attachable head composed of members havingdiametrically opposed recesses forming an aperture for receiving saidshank, said attachable head portion being secured in place upon saidshank, and spring contacts, terminals and an armature mounted upon saidattachable head portion, the terminals being electrically connected tosaid coil, and said armature fhaving a pole face disposed adjacent toone face of said rst mentioned head portion.

11. In a relay, a magnetic core arranged to receive a form wound coiland having a shank integral at one end thereof and a pole face at theDANIEL D. MILLER.

